diff --git a/Makefile b/Makefile
index 1c222cc..47270de 100644
--- a/Makefile
+++ b/Makefile
@@ -6,7 +6,7 @@
 #    By: kcolin <marvin@42.fr>                      +#+  +:+       +#+         #
 #                                                 +#+#+#+#+#+   +#+            #
 #    Created: 2024/10/14 13:43:59 by kcolin            #+#    #+#              #
-#    Updated: 2024/10/16 15:38:09 by kcolin           ###   ########.fr        #
+#    Updated: 2024/10/16 16:02:21 by kcolin           ###   ########.fr        #
 #                                                                              #
 # **************************************************************************** #
 
@@ -31,7 +31,8 @@ SOURCES = ft_isalpha.c \
 	ft_strncmp.c \
 	ft_memchr.c \
 	ft_memcmp.c \
-	ft_strnstr.c
+	ft_strnstr.c \
+	ft_atoi.c
 OBJECTS = $(SOURCES:.c=.o)
 CC = gcc
 
diff --git a/ft_atoi.c b/ft_atoi.c
new file mode 100644
index 0000000..2076acd
--- /dev/null
+++ b/ft_atoi.c
@@ -0,0 +1,45 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   ft_atoi.c                                          :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: kcolin <marvin@42.fr>                      +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2024/10/16 16:06:11 by kcolin            #+#    #+#             */
+/*   Updated: 2024/10/16 16:14:38 by kcolin           ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#include "libft.h"
+
+int	ft_atoi(const char *nptr)
+{
+	int	result;
+	int	i;
+
+	result = 0;
+	i = 0;
+	while (ft_isdigit(nptr[i]))
+	{
+		result *= 10;
+		result += nptr[i] - '0';
+		i++;
+	}
+	return (result);
+}
+
+/*
+#include <stdlib.h>
+#include <stdio.h>
+
+int	main(int argc, char **argv)
+{
+	if (argc > 1)
+	{
+		printf("mine: %d\nlib:  %d\n",
+			ft_atoi(argv[1]),
+			atoi(argv[1]));
+	}
+	return (0);
+}
+*/
diff --git a/libft.h b/libft.h
index c7277dc..a6c1987 100644
--- a/libft.h
+++ b/libft.h
@@ -6,7 +6,7 @@
 /*   By: kcolin <marvin@42.fr>                      +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2024/10/15 10:11:54 by kcolin            #+#    #+#             */
-/*   Updated: 2024/10/16 15:25:46 by kcolin           ###   ########.fr       */
+/*   Updated: 2024/10/16 16:06:06 by kcolin           ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -42,4 +42,6 @@ int		ft_memcmp(const void *s1, const void *s2, size_t n);
 
 char	*ft_strnstr(const char *big, const char *little, size_t len);
 
+int		ft_atoi(const char *nptr);
+
 #endif